Module i2c PCF8574A + LCD 16x2


#1

I have a PCF8574A module with a 16x2 LCD (CCM1620CSLS2), after several attempts without working, I measured the pin configuration and I see use P4 P5 P6 P7 for data, as seen in several examples that use P0 P1 P2 P3.

Parallel LCD works

With the gweimer / lcd-i2c-init library, it only works backligth

with the XOD node nothing


#2

That’s odd…gweimer library doesn’t do anything that XOD node doesn’t…it just provides opportunity to NOT do some of the functionality. If you set INIT to false, the backlight may just be defaulting to on & XOD node is doing a reset that turns it off.

P0-P7 are all used for data between PCF8574A & LCD. Are you sure data & clock pins for I2C are configured correctly and not swapped? Are you using the correct address (looks like 38h = 56d if you tie A0, A1, and A2 to ground; 3Fh = 63d if A0-A2 are tied to Vcc)?


#3

I will buy an LCD i2c, this combo will be for other experiments, the address is 3Fh.
First I thought it could be for a 1 in EN, but it was not that

thanks